Machine for original boring described and claimed therein

ABSTRACT

A horizontal boring machine is presented. The machine includes a pump which pumps mud forward through a hollow drill pipe and drill to form a seal on the outside of any casing which is used and to carry cuttings back through the casing. A one-way check valve in the drill pipe prevents mud from flowing back through the drill pipe. A flexible baffle within the casing maintains constant pressure within the casing near the drill. The casing may be moved along with, or independently and selectively ahead of or behind the drill by a hydraulically powered casing clamp. The forward portion of the casing terminates in a slanted shoe permitting control of the direction of boring by rotation of the casing.

United States Patent 119'] Taylor et al.

1 Nov. 5, 1974 1 1 MACHINE FOR ORIGINAL BORING DESCRIBED AND CLAIMED THEREIN 1221 Filed: Nov. 12, 1971 121 App1.No.:198,2 44

[52] US. Cl 175/73, 175/62, 175/80,

175/171,175/218,175/231 [51] Int. Cl E2lb 7/10 [58] Field 0f Search 175/25, 61, 62, 65, 66, 175/73, 76, 80, 170, 171, 218, 231, 234; 166/224 R 156] References Cited UNITED STATES PATENTS 2,485,826 10/1949 Harinck 175/171 X 2,588,068 3/1952 Williams et al 175/171 X 2,694,549 11/1954 James 175/73 X 2,716,018 8/1955 Williams 175/171 X 2,776,817 l/l957 Gregory et a1. 175/62 X 2,798,692 Thomas 175/62 X 3,289,691 12/1966 Kennard 166/224 X 3,356,167 12/1967 Trent 175/62 X 3,405,770 10/1968 175/65 X 3,610,346 10/1971 Ziober 175/171 X Primary ExaminerWerner l-l. Schroeder [57] ABSTRACT A horizontal boring machine is presented. The machine includes a pump which pumps mud forward through a hollow drill pipe and drill to form a seal on the outside of any casing which is used and to carry cuttings back through the casing. A one-way check valve in the drill pipe prevents mud from flowing back through the drill pipe. A flexible baffle within the casing maintains constant pressure within the casing near the drill. The casing may be moved along with, or independently and selectively ahead of or behind the drill by a hydraulically powered casing clamp. The forward portion of the casing terminates in a slanted shoe permitting control of the direction of boring by rotation of the casing.

3 Claims, 6 Drawing Figures Pmmimnv 51914 m m a UH ERC W0 5 ILW vi 4 mm a a .0 AR Y B 2 1 m ROBERT L. SASSONE ATTORNEY PAIENIEmnv 519M I 1845328 1 smear? I 66 FIG. 54

INVENTORS 46 2s 32 A. c. TAYLOR Y BY ROBERT w. CLARK H6. 4 ROBERT L. SASSONE ATTORNEY MACHINE FOR ORIGINAL BORING DESCRIBED AND CLAIMED THEREIN BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to horizontal earth boring and conduit laying machines.

2. Description of the Prior Art The prior art includes a wide variety of horizontal earth boring and casing laying machines. Many of these machines provide means for pushing casing through the bore which is drilled by the drill to prevent collapse of the bore. These machines can bore holes on a substantially horizontal plane or on a slightly inclinedplane and simultaneously position casing in the bore. These machines are particularly useful for digging under streets, railroad tracks, etc., without disturbing the surface or requiring the diversion of traffic.

Most of the prior art machines comprise-a stable base having torque generating means coupled thereto which rotate an auger. The auger rotates and cuts earth away from the front of the bore and removes cuttings from the bore. Stabilizing means are used to prevent the driving portion of the machine from rotating when torque is applied to the auger. The auger may be surrounded by a casing or conduit slightly larger in diameter than the diameter of the auger and extending essentially the length of the bore. In some cases, compressed air has been used to eject the cuttings from the bore. In some machines, the cuttings are mixed with water so as to fluidize the cuttings for easier ejectment by compressed air and to reduce dust.

Tracks and similar guide means are sometimes used to insure greater precision in drilling and to permit the use of a longer culvert tube or casing. Some machines utilize the pressure of a fluid to drive a bullet-shaped driving head to form the bore. Silverman, US. Pat. No. 3,422,631, 422, delivers a cement to the metal driving form which is forming the hole where it can be discharged around the periphery of the cup on the rear of the driving form. This cement serves to consolidate the earth material forming the wall of the conduit and cements at tubing to this consolidated earth conduit. Other prior art machines compress the earth to form the bore rather than removing the cuttings from the bore. Other prior artfmachines utilize expandable drills tocut bores of diameters greater than the casing through which the drill may be moved when contracted. I

The prior art for vertical drilling machines includes systems which forcemud down into the hole to lubricate the drill and to bring back cuttings from the drill to the surface. I

The prior art discloses no horizontal boring machine which simultaneously lubricates the drill head, provides full 100 percent sealing between the outside of the casing and the surrounding earth, maintains constant pressure inside the casing, or permits precise control of the direction of bore.

SUMMARY OF THE INVENTION A horizontal boring machine is presented. The machine includes a pump which pumps mud forward through a hollow drill pipe and drill to form a seal on the outside of any casing which is used and to carry cuttings back through the casing. A mud supply is formed in a shaker and mud supply from the mixing of water in dry mud or appropriate chemicals or from mud and cuttings from a bore. A one-way check valve in the drill pipe prevents mud from backing up within the drill pipe. Mud pumping means remove mud and cuttings from the bore. Pressure within the anulus formed between the drill pipe and the inner surface of the casing or bore (if no casing is used) is maintained by a flexible baffle which forms a pressure barrier to maintain pressure within the forward portion of the bore.

The casing may be moved along with, or independently and selectively ahead of or behind the drill by a hydraulically powered casing clamp. The casing clamp, which may have teeth, bites into the outer surface of the casing and transmits force to the casing from a spider which receives the force from a ram which in turn is powered by hydraulic of other power transmitted through an actuator. After the ram moves throughout its range, the casing clamp is released, the ram is moved back to the other end of its range, the casing clamp is once again affixed to the casing and moved by the ram. The casing and drill pipe may be coupled together to ensure that they are coaxial.

The drill is rotated by force transmitted through the drill pipe which in turn receives power from a movable power sub which may be powered by hydraulic or other power from a motor above ground. The power sub is moved longitudinally along a track by means such as a winch and cable which makes unnecessary the use of a kelly known to the prior art.

The direction of drilling is controlled by an asymmetrical cylindrical shoe. The forward tip of the shoe is cut back along the forward edge so that that portion near the forward tip exerts more pressure on the surrounding earth causing the forward edge of the casing coupled to the shoe to curve in the direction of the forward tip. Rotation-of the casing rotates the shoe to change the direction of drilling. The forward edge of the shoe may include teeth to increase the tendency of the shoe to curve the direction of the drilling. The force with which the shoe is pushed forward determines the rate of curvature of the bore.

Modifications of the example described herein will be obvious to those skilled in the art. The scope of the invention is limited onlyhby the claims of the present patent application.

DRAWING SUMMARY Reference should be made at this time to the following detailed description which should be read in conjunction with the following drawings:

FIG. 1 is a block diagram illustrating a horizontal boring machine according to the present invention;

FIG. 2 is a side view of the horizontal boring machine according to the present invention;

FIG. 3 is a side view taken along the lines 3-3 of FIG. 5;

FIG. 4 is a front view taken along the lines 4-4 of FIG. 2;

2 FIG. 5 is a top view taken along the lines 55 of FIG.

FIG. 6 is a partially cut away side view of the drill and forward portion of the casing of the invention.

DETAILED DESCRIPTION Reference should be made at this time to FIG. 1 which illustrates a partial block diagram of a horizontal boring machine according to the present invention, and to FIG. 2 which illustrates selected blocks in FIG. 1. A mud supply is formed in a shaker and mud supply 12 which separates solids from mud by shaking off the solids and letting the mud flow down through a screen. The mud is formed in a standard manner well known in the art by the mixing of water in dry mud or appropriate chemicals. The mud supply may also utilize mud and cuttings pumped up from the bore 34 via a mud return line 18. A motor 20 drives a pump 22 which pumps mud via a mud-pump line 24 through drill pipe 26 through a mud exit 28 in the drill 30 and out through casing 32. Casing 32 may be used to support the inside of the bore or tunnel 34 drilled by the drill 30. Forward refers to the longitudinal direction of drilling and the end closest to the drill 30.

Part of the mud 36 fills the empty space 40 formed between the bore wall 38 and the outer surface of the casing 32. The shape of the empty space 40 filled by the mud 36 is variable and depends upon the diameter or other cross-sectional shape of the casing 32 and the size of the bore 34 cut out by the drill 30. The mud 36 fills essentially all of the empty space 40 and lubricates the outer surface 42 of the casing 32 during rotation and longitudinal movement. Most of the mud 36 is not required to fill the space 40. The surplus mud 36 flows back around the drill 30 into the casing 32 and mixes with the cuttings 44 cut out from the surrounding earth as the drill 30 gradually lengthens the bore 34. No casing 32 is required for certain types of essentially horizontal boring in very hard earth such as rock. Where casing is required, the casing is generally cylindrical slightly less then the diameter of the bore 34 cut by the drill 30. In very soft soil, the casing 32 may even be advanced in front of the drill and the drill may drill inside the casing.

Where casing 32 is used, an annulus 46 is formed inside the casing 32 between the casing 32 and the drill pipe 26. Mud 36 and cutting 44 are forced back around the drill by the pressure from the mud pump into the annulus 46 formed between the casing 32 and drill pipe 26. Regardless of the up or down angle of the bore 34,

the mud pump 22 forces the mud 36 and cutting 44 out of the back end of the casing 32. The annulus 46 may be filled with mud 36 and cuttings 44 where the drilling is in a downhill direction. The quantity of mud 36 and cutting 44 within the annulus 46 has very little effect on the drilling procedure. Pressure within the annulus 46 may be maintained at a relatively constant level by a flexible baffle 48 which is made of, for example, relatively stiff rubber, bonded to the drill pipe 26 and which closes off a selected length of forward part of the annulus 46 near the drill. Pressure within the annulus 46 is determined primarily by the stiffness of the flexible baffle 48 because the mud pump 22 is powerful enough to overcome any pressure the baffle 48 can hold. A second mud pump 50 pumps the mud 36 mixed with cuttings 44 back up to the surface via the mud return line 18 which feeds a selected amount ofthe mixed mud 36 and cuttings 44 back to the shaker 12 for recycling. Under normal conditions, no one need be in the bore 34.

Reference should be made at this time to FIGS. 3, 4 and 5 which illustrate portions of the invention along the lines 3, 4 and 5 in FIGS. 2 and 5. The casing 32 may be moved into the bore 34 independently of forward progress of the drill 30. A casing clamp 54 is wrapped around the casing 32. The casing clamp 54 may be given stronger gripping qualities by the use of casing clamp teeth 58 which bite into the outer surface of the casing 32. Hydraulic or other power is transmitted to an actuator 62 which moves a ram 64. The ram 64 transmits power to a spider 60 which transmits the force to the casing 32 by means of the casing clamp 54. The ram 64 has a selected range which may be about 5 feet. After the ram 64 moves throughout its range, the casing clamp 54 is released, the ram 64 is moved back to the other end of its range, the casing clamp 54 is once again affixed to the casing 32, and the ram 64 again moves the casing 32 as described previously. The use of the casing clamp 54 permits the ram 64 to have a shorter range, which saves weight, materials and space. When the casing 32 has moved a sufficient distance into the bore 34, a new casing 32 segment is brought down into the hole where the machine 10 is stabilized and affixed to the previous casing by means known to the prior art such as welding. The length of casing segments which may be used is thus a function of convenience and the length of the machine 10, rather than the range of the ram 64.

The drill 30 is rotated by force transmitted through the drill pipe 26 which in turn receives power from a power sub 56. The power sub 56 may receive its power from a motor which may be above ground. For most purposes, power is best transmitted to the power sub 56 via a hydraulic pump 72 and appropriate hydraulic lines 74-78. Mud is transmitted from the mud-pump line 24 to the interior 27 of the drill pipe 26 via a chicksan swivel joint, not shown. The chick-san swivel joint is known to the prior art and is utilized to transmit fluids between the interiors of a pipe which is rotating and a pipe which is not rotating. The power sub 56 travels on a horizontal track as the drill pipe 26 moves into the tunnel 34 during drilling. The power sub 56 contains gears (not shown) which convert hydraulic or other power into torque which is used to rotate the drill 30 and drill pipe 26.

A winch 66 and cable 68 are coupled to the power sub 56 and the outside end of the drill pipe 26 in a well known manner in order to move the drill 30 into and out of the bore 34. The use of a winch and cable as opposed to rams reduces the amount of gearing up which is necessary to move the drill 30 as desired over long ranges. During operation, the power sub 56 is always coupled to the back end of the drill pipe 26.

The means described herein to move the drill pipe 26 and drill 30 and the casing 32 make unnecessary the use of a kelly which in the prior art is generally coupled to move casing and drill pipe and rotate the drill pipe.

A one-way check valve 52 permits flow of the mud only one way within the interior 27 of the drill pipe 26. The check valve may be conveniently placed inside a tool joint (not shown) on the drill pipe 26 near or in the vicinity of the drill.

A shoe on the forward end of the casing permits controlling of the direction of drilling. The shoe 80 may include shoe teeth 82 for greater efficiency. Normally in horizontal drilling, there is a tendency for the drill to gradually curve downward. The shoe 80 is cylindrical in cross section but has a forward end which is cut at an angle so that the front tip 84 of the shoe 80 extends further out than the rest of the shoe and the portions of the forward edge 86 of the shoe 80 closer to the tip 84 extend further than those portions of the forward edge 86 farther from the tip 84. The forward edge 86 of the shoe 80 thus exerts different controlled pressures on the surrounding earth. There is a tendency for the casing to curve in the direction of the forward tip 84. Accordingly, if the tip 84 is at the top of the bore 34, the shoe 80 will counteract the normal tendency of a horizontal drilling machine to curve the hole downward. If the shoe 80 is rotated to the right or left, there will be a tendency for the bore 34 to curve in the direction towards which the front tip 84 has been rotated. The force with which the shoe 80 is pushed forward determines the rate of curvature of the bore 34. A stabilizer (not shown) near the drill 30 maintains the drill 30 in the center line of the casing 32. For most purposes, the angle of the forward edge 86 of the shoe 80 should be about 45 and shoe teeth 82 should be utilized. The shoe 80may be welded to the forward portion of the most forward casing segment 32. The casing 32 may be rotated by putting a chain tong (not shown) around the casing 32. The end of the chain tong which somewhat resembles a wrench is then coupled to the line which lets casing 32 down into the hole. Pulling on the line which lets the casing 32 down into the hole causes the chain tong to rotate the casing 32 and change the orientation of the tip 84 of the shoe 80 to selectively control the direction of drilling within the limitations of the method.

The invention has been described in detail to provide a full public disclosure of several particular examples thereof. However, said detailed description is not intended in any way to limit the broad features or principles of the invention,-or the scope of the invention claimed. The scope of the invention is limited only by the following claims. What is claimed is: l. A horizontal boring machine comprising: hollow drill pipe capable of being moved linearly; a drill coupled to and rotated by the drill pipe; pumping means to pump mud to the forward end of the drill; I

movable power-sub means coupled to rotate the drill P me ans to control pressure inside the bore near the drill;

casing;

casing clamp means;

a spider;

means to longitudinally move the casing via the easing clamp means;

a shoe coupled to the forward portion of the casing;

means to rotate the casing and shoe in either direction around the drill pipe;

wherein the forward edge of the shoe is cut back from a front tip at about 45;

teeth on the forward edge of the shoe;

two rams which move the spider; and

hydraulic power means.

2. A horizontal boring machine comprising:

hollow drill pipe capable of being moved linearly;

a drill coupled to and rotated by the drill pipe; I

pumping means to pump mud to the forward end of the drill;

movable power-sub means coupled to rotate the drill a mud return which pumps mud and cutting from the casing to the shaker; I

means to return mud from the shaker to the pumping means; l

a winch and cable which move the power sub and drill pipe longitudinally in either direction; and

teeth on the interior surface of the casing clamp which teeth grip the casing.

3. A horizontal boring machine, comprising:

a drill;

hollow drill pipe coupled to and capable of rotating the drill;

means to move the drill and drill pipe longitudinally;

casing;

means to move the casing longitudinally;

means to pump mud to fill the space between the casing and the adjacent wall of the bore cut by the drill;

a mud pump which pumps mud to the forward end of the drill and forces the mud and cutting out of the back end of the casing;

a shaker;

a second mud pump which pumps the mud and cutting away from the back end of the casing to the shaker; and

means to return a portion of the mud and cutting pumped to the shaker from the shaker back to the first mud pump. 

1. A horizontal boring machine comprising: hollow drill pipe capable of being moved linearly; a drill coupled to and rotated by the drill pipe; pumping means to pump mud to the forward end of the drill; movable power-sub means coupled to rotate the drill pipe; means to control pressure inside the bore near the drill; casing; casing clamp means; a spider; means to longitudinally move the casing via the casing clamp means; a shoe coupled to the forward portion of the casing; means to rotate the casing and shoe in either direction around the drill pipe; wherein the forward edge of the shoe is cut back from a front tip at about 45*; teeth on the forward edge of the shoe; two rams which move the spider; and hydraulic power means.
 2. A horizontal boring machine comprising: hollow drill pipe capable of being moved linearly; a drill coupled to and rotated by the drill pipe; pumping means to pump mud to the forward end of the drill; movable power-sub means coupled to rotate the drill pipe; means to control pressure inside the bore near the drill; casing; casing clamp means; a spider; means to longitudinally move the casing via the casing clamp means; a flexible baffle inside the portion of the casing near the drill; a one-way check valve permitting mud flow through the drill pipe only toward the drill; a shaker; a mud return which pumps mud and cutting from the casing to the shaker; means to return mud from the shaker to the pumping means; a winch and cable which move the power sub and drill pipe longitudinally in either direction; and teeth on the interior surface of the casing clamp which teeth grip the casing.
 3. A horizontal boring machine, comprising: a drill; hollow drill pipe coupled to and capable of rotating the drill; means to move the drill and drill pipe longitudinally; casing; means to move the casing longitudinally; means to pump mud to fill the space between the casing and the adjacent wall of the bore cut by the drill; a mud pump which pumps mud to the forward end of the drill and forces the mud and cutting out of the back end of the casing; a shaker; a second mud pump which pumps the mud and cutting away from the back end of the casing to the shaker; and means to return a portion of the mud and cutting pumped to the shaker from the shaker back to the first mud pump. 